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Are Breathalyzers Accurate in California?

Breathalyzers are not 100% accurate all the time. Law enforcement and the courts know that they are not always 100% correct and accept the margin of error involved. Unfortunately for you, if you are the subject of the inaccurate test, the police and prosecutors will treat you just like anyone who failed a breath test.  

There are a number of problems with relying on portable alcohol screening devices (PAS devices) and the larger breath testing machines at police stations. These devices can fail due to operator error or not being calibrated. 

If you submitted to a roadside breath test or gave a breath sample when arrested for a DUI in California, there may be a number of reasons why those test results are not accurate. Contact an experienced East Bay criminal defense lawyer to review your case and challenge the breath test evidence.  

How Can Technologically Advanced Breath Testing Machines Fail?

Like any new technology, there are potential problems with accuracy and integrity that may not appear at first or only occur occasionally. There could be a software bug that gives an error message or fails to properly calibrate the device. Being dropped a few times could cause damage to the device, including problems with measuring or calibration. Even if a machine works 99 times out of 100, it is not fair to the number 100 suspect who has to face serious criminal penalties associated with a DUI conviction

Many times, a failed breath test is not even the fault of the device. The machine could be working perfectly well, the officer could conduct the test according to the rules, and the driver could properly give a breath test. 

Non-Drinking Related Factors 

Unfortunately, there are a number of reasons an individual may test with a blood alcohol content (BAC) above the legal limit even if they did not drink enough alcohol to put them over the limit. Non-drinking related causes of inaccurate breath testing devices can include: 

  • Medications, 
  • Mouthwash,
  • Gum or mints, 
  • Medical issues, 
  • Diabetes-related issues, or
  • Acid reflux or burping. 

If there is a problem with the machine, are the police going to tell you about it?

The real benefits of an experienced DUI defense lawyer are that they will investigate your case and not just take the prosecutor's word for it. If there has been a problem with the breath testing device, the police are not likely to tell you about this. They will provide the test results and criminal investigation evidence to the prosecutor and the prosecutor will decide whether to go forward with criminal charges. 

Your attorney can get a copy of the records, including any video or audio records that go along with the arrest. Your attorney may also be able to get the records associated with the testing device, including when and how often it was serviced, calibrated, or updated. If there is anything out of the ordinary, a problem with the procedures, or cause to question the accuracy of the test results, your attorney can file a motion to suppress the evidence and keep it out of your case. 

How can the police use breath test evidence if it is not 100% reliable?

Breath tests may not be 100% reliable all of the time. The courts generally accept the margin of error associated with these tests but try and minimize the margin by making sure the equipment is properly maintained, calibrated, cleaned, and operated according to proper procedures. 

However, even the courts do not rely on the PAS breath testing devices that police use during traffic stops as evidence in court. It can be confusing for drivers to understand the difference. Roadside breath tests are generally not mandatory (except for some young drivers or drivers on probation). The PAS breath test results are used for the police to give them enough of a reason to make an arrest. However, these results are not used in court as evidence of the driver's actual blood-alcohol level. 

Instead, the larger breath testing devices that are used after a driver is arrested are used for evidentiary purposes. These breath tests are not optional and a driver who refuses a breath test sample after arrest can face mandatory penalties, including a suspended license. Failure to submit to the breath test can also be used in court. 

East Bay Criminal Defense Attorney Lynn Gorelick

To ensure you have the best chance at avoiding an unfair conviction, East Bay attorney Lynn Gorelick will look for problems with the breath testing evidence to help you avoid a criminal record. With more than 35 years of California criminal defense experience, contact Lynn Gorelick today for help with your Alameda County DUI or other criminal charges.

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